FAQ on Access Everywhere Network (ACEnet) and Wireless Local Area Network (WLAN)

Refer to http://www.itservices.hku.hk/home/networks/wifi.htm

Remove all wireless network names detected by your notebook and let it detects "Universities" "CC WLAN" again. Also, Use Windows to configure my wireless setting. This would help to solve the problem.

Check the following:

1. You must first configure your PC for connecting to the campus network.

2. There may be problems with the IP address of your PC.

(i) You must configure your PC to "obtain an IP address automatically".

(ii) A previous IP address may have been retained in your PC. Click here to see how to obtain an IP address automatically from the DHCP server.

3. Login the HKUVPN gateway using your Network password for special programs (e.g. MSN Messenger webcam, Apple iChat). 
(Click here for a list of the applications that do not require login HKUVPN.)

Q5.1: I received a NETWORK ABUSE warning from the Computer Centre and now I cannot connect to the network

If you abused the HKU network (spreading a virus, port scanning, using excessive network bandwidth etc), your network account or network card may be disabled. You must clean up the virus or trojan horse, then re-activate your network card in the HKU Portal => Campus Information Services => Central IT Services => click the link Restore Network Access.

If you still cannot connect to the network after trying the above steps, send an email to abuse@hku.hk to enquire whether your network port was disabled or not.

I never received any ABUSE warning but still cannot connect to the network

Some anti-spyware (e.g. PC-cillin) or firewall software may block all network traffics due to mis-configuration. If you have newly installed any anti-spyware or firewall software, you should check the configurations carefully, or temporarily disable the software to see if the network blockage is due to the software.

Q5.2: Sometimes I can't login the HKUVPN network even though my account information is correct

Select "Never dial a connection" in your Internet Explorer (IE) browser :
In IE, click menu Tools
=> Internet Options
=> Connections
=> select "Never dial a connection"

To register your network card under the HKU Portal, you need to reveal the network card address of your PC:

For Windows Vista:

How to find out the Ethernet address through the Network and Sharing Center:

1. Click Windows Start => right-click on Network => click Properties.
2. A Network and Sharing Center window will open. Click View status to the right of Local Area Connection (cable) or Wireless Network Connection (wireless).
3. In the new Local Area Connection Status window that opens, click Details.
The Physical Address is its Ethernet address.
4. Register the Ethernet address (12 characters without the hyphens) under HKU Portal. (See Question 1 on how to do so.)

How to find out the Ethernet address through the Command Prompt:

Click here to watch video on how to find out the Ethernet address.


1. Click Windows Start => All Programs => Accessories => Run (or press 'Windows Logo' key + 'R' keys)
2. Type in the word cmd , and click OK
3. Once a black command window appears, type in ipconfig /all and hit the Enter key.
4. To register your Wireless network card, look under the Ethernet adapter Wireless Network Connection section and the Physical Address is its Ethernet address.

   To register your wired network card (connection using a cable), look under the Ethernet adapter Local Area Connection section and the Physical Address is its Ethernet address.

5. Register the Ethernet address (12 characters without the hyphens) under HKU Portal. (See Question 1 on how to do so.)

To obtain a new IP address from the DHCP server, type in ipconfig /release and then type in ipconfig /renew

For Windows XP:

1. Click Windows Start => Run
2. Type in the word cmd , and click OK
3. Once a black command window appears, type in ipconfig /all and hit the Enter key.
4. To register your Wireless network card, look under the Ethernet adapter Wireless Network Connection section and the Physical Address is its Ethernet address.

   To register your wired network card (connection using a cable), look under the Ethernet adapter Local Area Connection section and the Physical Address is its Ethernet address.

5. Register the Ethernet address (12 characters without the hyphens) under HKU Portal.

To obtain a new IP address from the DHCP server, type in ipconfig /release and then type in ipconfig /renew

NOTE: For other systems such as Apple Macintosh OS, iPhone, iPod Touch and Linux (Asus Eee PC), see http://www.itservices.hku.hk/faq/register-nic.htm#q3

A DNS (Domain Name Server) resolves a computer domain name into its IP address which is used to identify and reach a computer on the network. By default, you should obtain an IP address (including the DNS setting) automatically from the DHCP server. However, if you get a network error for some reason, you may have to configure the DNS setting explicitly as follows. Note: the explicit DNS setting may be changed without prior notice.

For Windows Vista:

1.Click Windows Start => Control Panel
2. Click Network and Internet => Network and Sharing Center. In the left pane, click Manage network connections.
3.Right-click the connection that you want to change, and then click Properties. If you are prompted for an administrator password or confirmation, type the password or provide confirmation.
4. In "Internet Protocol Version 4 (TCP/IPv4) Properties" window, click the Networking tab.
5. Under "This connection uses the following items", click Internet Protocol Version 4 (TCP/IPv4) and then click Properties.
6. Select the radio button "Use the following DNS server addresses"
7. Enter Preferred DNS server: 147.8.145.30, Alternate DNS server: 147.8.2. 2
8. Click the OK button to exit to the "Internet Protocol Version 4 (TCP/IPv4) Properties" window.
9. Click the Close button. Restart your PC to make this new configuration take effect.

For Windows XP:

1. Double click on the My Computer icon => Control Panel folder.
2. Click on the Network Connections icon.
3. Right-click the connection that you want to change, and then click Properties.
4. Under "This connection uses the following items", click TCP/IP and then click Properties.
5. Select the radio button "Use the following DNS server addresses"
6. Enter Preferred DNS server: 147.8.145.30, Alternate DNS server: 147.8.2. 2
7. Click the OK button to exit to the TCP/IP dialog box.
8. Click the OK button. Restart your PC to make this new configuration take effect.

An orange label with a notebook computer symbol is sticked on an ACEnet socket box, but not on other network point socket boxes.

You must not assign an explicit IP address in your computer. Instead, select "Obtain an IP address automatically" for "TCP/IP"

For Windows Vista:

1.Click Windows Start => Control Panel
2. Click Network and Internet => Network and Sharing Center. In the left pane, click Manage network connections.
3.Right-click the type of connection (Local Area Network or Wireless Network), and then click Properties. If you are prompted for an administrator password or confirmation, type the password or provide confirmation.
4. Select Internet Protocol Version 4 (TCP/IPv4) and then click Properties.
5. In "Internet Protocol Version 4 (TCP/IPv4) Properties" window, select Obtain an IP address automatically and Obtain DNS server address automatically
6. Click the OK button to exit to the "Internet Protocol Version 4 (TCP/IPv4) Properties" window.
7. Click the Close button.

For Windows XP:

1. Double click on the My Computer icon => Control Panel folder.
2. Click on the Network Connections icon.
3. Right-click the connection that you want to change, and then click Properties.
4. Under "This connection uses the following items", click TCP/IP and then click Properties.
5. In "Internet Protocol (TCP/IP) Properties" window, select Obtain an IP address automatically and Obtain DNS server address automatically.
6. Click OK to close all windows.

Macintosh (OS X):

1. Select Apple Menu => System Preferences => Network button.
2. Select TCP/IP tab and configure Using DHCP
3. Above the TCP/IP Tab, you may need to configure via AirPort or other wireless (WiFi) Ethernet.
4. Leave Domain Name Servers and Search Domains blank.

Note: The network card in your PC must be registered beforehand.

When two people use the same IP address on the Internet, there is an IP address conflict.

Do not hard code the IP Address in your computer. Select 'Obtain an IP address automatically' in the TCP/IP setting. If the problem does not go away, copy down the Ethernet Address of the other network user and pass the information to the Help Desk of the Computer Centre (Tel. 2859-2480) or send email to ithelp@hku.hk.

Query the network card address of the other user as follows:

For Windows Vista:
Click Windows Start => Control Panel => double click on Administrative Tools => Event Viewer => Windows Log => System => right-click on the Error icon (in red) => select Properties, and the network card address of the other user will be displayed in the error description window.

For Windows XP:
Click Start => Settings => Control Panel => double click on Administrative Tools => Event Viewer => System Log => right-click on the Error icon (in red) => select Properties, and the network card address of the other user will be displayed in the error description window.

Click here to see how to reveal your own network card address.

If a Network Bridge is present, right-click on "Network Bridge" icon. On the drop down menu, click Delete. A PC should not be a network bridge in the HKU network environment.

For Windows Vista:

1.Click Windows Start button => Control Panel folder.
2. Click Network and Internet => Network and Sharing Center. In the left pane, click Manage network connections.
3.Right-click the shared connection and then click Properties. If you are prompted for an administrator password or confirmation, type the password or provide confirmation.
4. Click the Sharing tab, clear the Allow other network users to connect through this computer's Internet connection check box, and then click OK.
5. Repeat step 3 and 4 for all interfaces including LAN, Wireless and VPN.
6.Do not set up a home or small office network in HKU network environment.

For Windows XP:

1. Double click on the My Computer icon, open the Control Panel folder.
2. Click on the Network Connections icon.
3. Right-click the shared connection and then click Properties.
4. Click the Advanced tab, clear the Allow other network users to connect through this computer's Internet connection check box, and then click OK.
5. Repeat step 3 and 4 for all interfaces including LAN, Wirel ess and VPN.
6. Do not set up a home or small office network in HKU network environment.

There are two modes of operation for Windows XP in a network: Workgroup or Domain. Workgroup requires a unique SID to facilitate and protect resources sharing among Workgroup users.  If you bought the notebook computer through HKU and you wish to work in the Workgroup mode, you will need to regenerate a unique SID since the notebook computer from the factory all have the same SID.  (Note: Same SID, e.g. the default from a computer's factory setting, would allow other users' computers with the same SID to read/write your shared files.)

1. Download a SID generator "NewSID" from this URL:

http://www.sysinternals.com/ntw2k/source/newsid.shtml

2. Unzip the downloaded NewSID in a temporary directory, e.g. C:\temp\

3. Click Windows Start => Run => cmd => Type in c:\temp\newsid /a and press Enter key to auto-run it. The procedure runs without prompting and rebooting the system if everything goes okay.